(a) Technical Field
The present invention relates to a multi-scaled oxygen storage material wherein cobalt or cobalt oxide is complexed with a size of an atom or hundreds of nanometers or smaller in a ceria-zirconia solid solution and a method for preparing the same.
(b) Background Art
Materials having oxygen storage capacity (OSC) are applicable to various industries including three-way catalysts, fuel cells, preparation of synthesis gases, etc.
Ceria-zirconia (CeO2—ZrO2, CZO)-based oxygen storage materials are representative examples because they exhibit high OSC close to about 740 μmol-O/g at 500° C. depending on the composition of CeO2 and ZrO2.
However, it is assessed that further improvement of OSC of the ceria-zirconia (CZO)-based oxygen storage materials is impossible due to the materials' limitations.
Korean Patent Registration No. 10-0738676 (hereinafter, referred to as ‘the patent document’) discloses a catalyst with improved activity for wet oxidation of hardly degradable wastewater, wherein a transition metal such as manganese (Mn), iron (Fe), cobalt (Co), etc. is supported on a ceria-zirconia solid solution as a support.
However, the patent document merely uses the ceria-zirconia solid solution with high OSC as a support for the transition metal and does not improve the OSC of the ceria-zirconia solid solution.
As stated above, the prior art focuses only on the use of ceria-zirconia (CZO)-based oxygen storage materials and there have not been many studies on the improvement of the materials themselves.